Files
reactics/smt/smt_checker_rsc.py
2017-03-05 17:41:26 +01:00

493 lines
19 KiB
Python

"""
SMT-based Model Checking Module for RS with Concentrations and Context Automaton
"""
from z3 import *
from time import time
from sys import stdout
from itertools import chain
import resource
from colour import *
import logics
# def simplify(x):
# return x
class SmtCheckerRSC(object):
def __init__(self, rsca):
rsca.sanity_check()
if not rsca.is_with_concentrations():
raise RuntimeError("RS and CA with concentrations expected")
self.rs = rsca.rs
self.ca = rsca.ca
self.v = []
self.v_ctx = []
self.ca_state = []
self.next_level_to_encode = 0
self.solver = Solver()
self.verification_time = None
def prepare_all_variables(self):
"""Encodes all the variables"""
self.prepare_state_variables()
self.prepare_context_variables()
self.next_level_to_encode += 1
def prepare_context_variables(self):
"""Encodes all the context variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Int("C"+str(level)+"_"+entity))
self.v_ctx.append(variables)
def prepare_state_variables(self):
"""Encodes all the state variables"""
level = self.next_level_to_encode
variables = []
for entity in self.rs.background_set:
variables.append(Int("L"+str(level)+"_"+entity))
self.v.append(variables)
self.ca_state.append(Int("CA"+str(level)+"_state"))
def enc_concentration_levels_assertion(self, level):
"""Encodes assertions that (some) variables need to be >0
We do not need to actually control all the variables,
only those that can possibly go below 0.
"""
enc_nz = True
for e_i in range(len(self.rs.background_set)):
v = self.v[level][e_i]
v_ctx = self.v_ctx[level][e_i]
e_max = self.rs.get_max_concentration_level(e_i)
enc_nz = simplify(And(enc_nz, v >= 0, v_ctx >= 0, v <= e_max, v_ctx <= e_max))
return enc_nz
def enc_init_state(self, level):
"""Encodes the initial state at the given level"""
rs_init_state_enc = True
for v in self.v[level]:
rs_init_state_enc = simplify(And(rs_init_state_enc, v == 0)) # the initial concentration levels are zeroed
ca_init_state_enc = self.ca_state[level] == self.ca.get_init_state_id()
init_state_enc = simplify(And(rs_init_state_enc, ca_init_state_enc))
return init_state_enc
def enc_produced_concentration(self, level, prod_entity):
"""Encodes the produced concentrations for the given level and entity"""
rcts_for_prod_entity = []
if prod_entity in self.rs.get_reactions_by_product():
rcts_for_prod_entity = self.rs.get_reactions_by_product()[prod_entity]
meta_reactions = []
if prod_entity in self.rs.meta_reactions:
meta_reactions = self.rs.meta_reactions[prod_entity]
permanency_inhibition = None
if prod_entity in self.rs.permanent_entities:
permanency_inhibition = self.rs.permanent_entities[prod_entity]
if rcts_for_prod_entity == [] and meta_reactions == []:
return simplify(self.v[level+1][prod_entity] == 0) # this should never happen
enc_enabledness = False
# ----------- ordinary reactions --------------------------------------------
enc_rct_prod = False
enc_ordinary_reactions_enabledness = False
for reactants,inhibitors,products in rcts_for_prod_entity:
enc_reactants = True
for reactant,concentration in reactants:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
enc_inhibitors = True
for inhibitor,concentration in inhibitors:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
enc_rct_enabled = And(enc_reactants, enc_inhibitors)
enc_products = self.v[level+1][products[0][0]] == products[0][1]
enc_rct_prod = simplify(If(enc_rct_enabled, enc_products, enc_rct_prod))
enc_enabledness = simplify(Or(enc_enabledness, enc_rct_enabled))
enc_ordinary_reactions_enabledness = simplify(Or(enc_ordinary_reactions_enabledness,enc_rct_enabled))
# for reactants,inhibitors,products in rcts_for_prod_entity:
# enc_reactants = True
# enc_inhibitors = True
# # enc_products -- below
#
# for reactant,concentration in reactants:
# enc_reactants = simplify(And(enc_reactants,
# Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
# for inhibitor,concentration in inhibitors:
# enc_inhibitors = simplify(And(enc_inhibitors,
# And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
#
# enc_products = self.v[level+1][products[0][0]] == products[0][1]
#
# enc_enabledness = simplify(Or(enc_enabledness, And(enc_reactants, enc_inhibitors)))
# enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_reactants, enc_inhibitors, enc_products)))
# -------- meta reactions ---------------------------------------------------
for r_type,command_entity,reactants,inhibitors in meta_reactions:
# command entity is e.g. 'inc' for incrementation operation
# (inc,W) gives us the value W by which the given entity's value should be incremented
enc_reactants = True
enc_inhibitors = True
for reactant,concentration in reactants:
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][reactant] >= concentration, self.v_ctx[level][reactant] >= concentration)))
# command entity needs to be present (with concentration level > 0) in order to perform the operation
enc_reactants = simplify(And(enc_reactants,
Or(self.v[level][command_entity] > 0, self.v_ctx[level][command_entity] > 0)))
for inhibitor,concentration in inhibitors:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
if r_type == "inc":
value_after_inc = If(self.v[level][prod_entity]>self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]) + \
If(self.v[level][command_entity]>self.v_ctx[level][command_entity],self.v[level][command_entity],self.v_ctx[level][command_entity])
enc_products = self.v[level+1][prod_entity] == value_after_inc
elif r_type == "dec":
value_after_dec = simplify(If(self.v[level][prod_entity]>self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]) - \
If(self.v[level][command_entity]>self.v_ctx[level][command_entity],self.v[level][command_entity],self.v_ctx[level][command_entity]))
enc_products = self.v[level+1][prod_entity] == If(value_after_dec < 0, 0, value_after_dec)
else:
raise RuntimeError("Unknown meta-reaction type: " + repr(r_type))
enc_meta_reaction_enabledness = And(enc_reactants, enc_inhibitors, Not(enc_ordinary_reactions_enabledness))
enc_enabledness = simplify(Or(enc_enabledness, enc_meta_reaction_enabledness))
enc_rct_prod = simplify(Or(enc_rct_prod, And(enc_meta_reaction_enabledness, enc_products)))
# -----------------------------------------------------------------------------
if not permanency_inhibition == None:
enc_reactants = Or(self.v[level][prod_entity] >= concentration, self.v_ctx[level][prod_entity] >= concentration)
enc_inhibitors = True
for inhibitor,concentration in permanency_inhibition:
enc_inhibitors = simplify(And(enc_inhibitors,
And(self.v[level][inhibitor] < concentration, self.v_ctx[level][inhibitor] < concentration)))
enc_products = simplify(self.v[level+1][prod_entity] == \
If(self.v[level][prod_entity] > self.v_ctx[level][prod_entity],self.v[level][prod_entity],self.v_ctx[level][prod_entity]))
enc_permanency_enabledness = And(enc_reactants, enc_inhibitors, Not(enc_ordinary_reactions_enabledness))
enc_enabledness = simplify(Or(enc_enabledness, enc_permanency_enabledness))
enc_permanency = And(enc_permanency_enabledness, enc_products)
enc_rct_prod = simplify(Or(enc_rct_prod, enc_permanency))
# -----------------------------------------------------------------------------
enc_when_to_produce_zero_conc = simplify(And(Not(enc_enabledness), self.v[level+1][prod_entity] == 0))
enc_rct_prod = Or(enc_rct_prod, enc_when_to_produce_zero_conc)
return enc_rct_prod
# def enc_entity_production(self, level, prod_entity):
# """Encodes the production of a given entity from a given level at level+1"""
#
# enc_enab_cond = self.enc_enabledness(level, prod_entity)
#
# enc_ent_prod = Or(And(enc_enab_cond, self.v[level+1][prod_entity]),
# And(Not(enc_enab_cond), Not(self.v[level+1][prod_entity])))
#
# return simplify(enc_ent_prod)
def enc_transition_relation(self, level):
return simplify(And(self.enc_rs_trans(level), self.enc_automaton_trans(level)))
def enc_rs_trans(self, level):
"""Encodes the transition relation"""
unused_entities = set(range(len(self.rs.background_set)))
enc_trans = True
reactions = self.rs.get_reactions_by_product()
meta_reactions = self.rs.meta_reactions
for prod_entity in chain(reactions, meta_reactions):
unused_entities.discard(prod_entity)
enc_trans = simplify(And(enc_trans, self.enc_produced_concentration(level, prod_entity)))
for prod_entity in unused_entities:
enc_trans = simplify(And(enc_trans, self.v[level+1][prod_entity] == 0))
return enc_trans
def enc_automaton_trans(self, level):
"""Encodes the transition relation for the context automaton"""
enc_trans = False
for src,ctx,dst in self.ca.transitions:
src_enc = self.ca_state[level] == src
dst_enc = self.ca_state[level+1] == dst
all_ent = set(range(len(self.rs.background_set)))
incl_ctx = set([e for e,c in ctx])
excl_ctx = all_ent - incl_ctx
ctx_enc = True
for e,c in ctx:
ctx_enc = simplify(And(ctx_enc, self.v_ctx[level][e] == c))
for e in excl_ctx:
ctx_enc = simplify(And(ctx_enc, self.v_ctx[level][e] == 0))
cur_trans = simplify(And(src_enc, ctx_enc, dst_enc))
enc_trans = simplify(Or(enc_trans, cur_trans))
return enc_trans
def enc_exact_state(self, level, state):
"""Encodes the state at the given level with the exact concentration values"""
raise RuntimeError("Should not be used with RSC")
# enc = True
# used_entities_ids = self.rs.get_state_ids(state)
#
# for ent,conc in state:
# e_id = self.rs.get_entity_id(ent)
# enc = And(enc, self.v[level][e_id] == conc)
#
# not_in_state = set(range(len(self.rs.background_set)))
# not_in_state = not_in_state.difference(set(used_entities_ids))
#
# for entity in not_in_state:
# enc = And(enc, self.v[level][entity] == 0)
#
# return simplify(enc)
def enc_min_state(self, level, state):
"""Encodes the state at the given level with the minimal required concentration levels"""
enc = True
for ent,conc in state:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] >= conc)
# state_ids = self.rs.get_state_ids(state)
#
# for entity in state_ids:
# enc = And(enc, self.v[level][entity])
return simplify(enc)
def enc_state_with_blocking(self, level, prop):
"""Encodes the state at the given level with blocking certain concentrations"""
required,blocked = prop
enc = True
for ent,conc in required:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] >= conc)
for ent,conc in blocked:
e_id = self.rs.get_entity_id(ent)
enc = And(enc, self.v[level][e_id] < conc)
return simplify(enc)
def decode_witness(self, max_level, print_model=False):
m = self.solver.model()
if print_model:
print(m)
for level in range(max_level+1):
print("\n{: >70}".format("[ level=" + repr(level) + " ]"))
print(" State: {", end=""),
for var_id in range(len(self.v[level])):
var_rep = repr(m[self.v[level][var_id]])
if not var_rep.isdigit():
raise RuntimeError("unexpected: representation is not a positive integer")
if int(var_rep) > 0:
print(" " + self.rs.get_entity_name(var_id) + "=" + var_rep, end="")
# print(" " + repr(m[self.v[level][var_id]]), end="")
print(" }")
if level != max_level:
print(" Context set: ", end="")
print("{", end="")
for var_id in range(len(self.v[level])):
var_rep = repr(m[self.v_ctx[level][var_id]])
if not var_rep.isdigit():
raise RuntimeError("unexpected: representation is not a positive integer")
if int(var_rep) > 0:
print(" " + self.rs.get_entity_name(var_id) + "=" + var_rep, end="")
print(" }")
def check_rsltl(self, formula, print_witness=True):
"""Bounded Model Checking for rsLTL properties"""
def dummy_unroll(self, levels):
"""Unrolls the variables for testing purposes"""
for i in range(levels):
self.prepare_all_variables()
print(C_MARK_INFO + " Dummy Unrolling done.")
def check_reachability(self, state, print_witness=True,
print_time=True, print_mem=True, max_level=1000):
"""Main testing function"""
if print_time:
# start = time()
start = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.prepare_all_variables()
self.solver.add(self.enc_init_state(0))
current_level = 0
self.prepare_all_variables()
self.solver.add(self.enc_concentration_levels_assertion(0))
while True:
self.prepare_all_variables()
self.solver.add(self.enc_concentration_levels_assertion(current_level+1))
print("\n{:-^70}".format("[ Working at level=" + str(current_level) + " ]"))
stdout.flush()
# reachability test:
print("[" + colour_str(C_BOLD, "i") + "] Adding the reachability test...")
self.solver.push()
self.solver.add(self.enc_state_with_blocking(current_level,state))
result = self.solver.check()
if result == sat:
print("[" + colour_str(C_BOLD, "+") + "] " + colour_str(C_GREEN, "SAT at level=" + str(current_level)))
if print_witness:
print("\n{:=^70}".format("[ WITNESS ]"))
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[" + colour_str(C_BOLD, "i") + "] Unrolling the transition relation")
self.solver.add(self.enc_transition_relation(current_level))
print("{:->70}".format("[ level=" + str(current_level) + " done ]"))
current_level += 1
if current_level > max_level:
print("Stopping at level=" + str(max_level))
break
if print_time:
# stop = time()
stop = resource.getrusage(resource.RUSAGE_SELF).ru_utime
self.verification_time = stop-start
print()
print("\n[i] {: >60}".format(" Time: " + repr(self.verification_time) + " s"))
if print_mem:
print("[i] {: >60}".format(" Memory: " + repr(resource.getrusage(resource.RUSAGE_SELF).ru_maxrss/(1024*1024)) + " MB"))
def get_verification_time(self):
return self.verification_time
def show_encoding(self, state, print_witness=True,
print_time=False, print_mem=False, max_level=100):
"""Encoding debug function"""
self.prepare_all_variables()
init_s = self.enc_init_state(0)
print(init_s)
self.solver.add(init_s)
current_level = 0
self.prepare_all_variables()
while True:
self.prepare_all_variables()
print("-----[ Working at level=" + str(current_level) + " ]-----")
stdout.flush()
# reachability test:
print("[i] Adding the reachability test...")
self.solver.push()
s = self.enc_min_state(current_level,state)
print("Test: ", s)
self.solver.add(s)
result = self.solver.check()
if result == sat:
print("\n[+] " + colour_str(C_RED, "SAT at level=" + str(current_level)))
if print_witness:
self.decode_witness(current_level)
break
else:
self.solver.pop()
print("[i] Unrolling the transition relation")
t = self.enc_transition_relation(current_level)
print(t)
self.solver.add(t)
print("-----[ level=" + str(current_level) + " done ]")
current_level += 1
if current_level > max_level:
print("Stopping at level=" + str(max_level))
break
else:
x=input("Next level? ")
x=x.lower()
if not (x == "y" or x == "yes"):
break